Field of Invention
The present invention relates to a damper device.
Background Information
Various devices are installed in a drivetrain of a vehicle to transmit power generated in an engine to a transmission. A damper device and a flywheel assembly can be exemplified as these types of devices. Damper devices are used for these devices to attenuate rotary vibrations (see Japan Laid-open Patent Application Publication No. JP-A-2012-159111).
The aforementioned damper device mainly includes an input-side rotary member (a first side plate and a second side plate), an output-side rotary member (a center plate), a plurality of coil springs to be compressed between the first side plate and the center plate, and an intermediate plate for coupling the coil springs.
When multistage torsional characteristics are set for this type of damper device, one or more bent points of the torsional characteristics, the upper limit of a torsion angle and so forth, are often set by causing coiled parts of intended ones of the plural coil springs to be closely contacted to each other. In this case, however, the coil springs can be damaged or broken by repeatedly causing the coiled parts of the coil springs to be closely contacted to each other.
On the other hand, to solve the aforementioned drawback, there has been developed a technology for mechanically deactivating the coil springs with use of the input-side rotary member and the output-side rotary member. In a stopper mechanism as an example of this technology, the coil springs are configured to be deactivated by causing the input-side rotary member and the output-side rotary member to contact each other. In this case, however, collision sounds are produced when the input-side rotary member and the output-side rotary member are contacted.
For example, the aforementioned stopper mechanism is configured to be activated when large torque is abruptly inputted into the input-side rotary member under a condition that a small torsion angle is produced (small torque is produced) between the input-side rotary member and the output-side rotary member. Accordingly, collision sounds are produced as described above. Hence, it is expected to establish a technology for lessening the collision sounds.